Digging teeth for excavating dippers, etc.



May 3, 1960 L. w. VAN BUSKlRK 2,

DIGGING TEETH FOR EXCAVATING DIPPERS, ETC.

Filed Nov. so, 1955 3 Sheets-Sheet 1 INVENTO;(. L W Van Bus/(17kATTORNEYS May 3, 1960 L. W. VAN BUSKIRK DIGGING TEETH FOR EXCAVATINGDIPPERS, ETC.

Filed NOV. 30, 1955 5 Sheets-Sheet 2 as a9 9' 2 6 39 I I I I May 3, 1960L. w. VAN B USKIRK DIGGING TEETH FOR EXCAVATING DIPPERS, ETC.

Filed Nov. 30, 1955 5 Sheets-Sheet 3 ATTORNEYS Unite States Patent2,934,842 1C Patented May a. 196

2,934,842 DIGGING TEETH EDIE: EiCAVATmG DIPPERS, T

V Lesher W. Van Buskirk, Easton, Pa. Y Application November 30, 1955,Serial No. 550,027

16 Claims. (Cl; 37-142) My invention relates to improvements in diggingteeth ofthe replaceable digging point type such as are disclosed in myapplication Serial Number 455,199, filed September 10, 1954 (Patent No.2,891,333, dated June 23, 1959), and are carried by the digging lip ofpower shovel dippers, drag buckets, etc. My present development aimsparticularly to improve over the disclosures of said application.

Digging teeth as characterized usually comprise, as in my aforesaidapplication, a base section which is secured to the digging lip of thedipper or bucket. The forward end of said base section provides a noseform seat to which is detachably secured the V-form digging point, ortip, which latter provides the divergent top and bottom seatembra cingwings. Such a tip requires more or less frequent replacement, dependingupon the character of material being dug.

In excavating operations involving rock or coal, the digging points ofthese teeth are subjected to tremendous stresses along lines originatingfrom points forwardly of their base sections and from both vertical andlateral directions with respect to the longitudinal axis of the tooth.This means that if the interfitted or seat-providing portions of thetooth base and tip do not provide for adequate stress transfer from thetip to the base from all directions forwardly of the latter, there willbe overloading of cer 'tain base-carried portions of the tip and theultimate breaking loose of the latter.

Then, too, if the key or other tip and base securing means does notretain said parts tightly together, a pounding action will be set up inservice to result in ultimate loss of the digging tip. A broken offdigging tooth tip may becomea dangerous piece of metal because if itsubsequently gets into expensive rock or coal crushing machinery it cancause great damage thereto, necessitating a shut-down of operations forcostly repairs.

Therefore, manufacturers of excavating equipment and others have devotedmuch time and effort to achieve satisfactory tooth base-provided diggingtip support against the stresses mentioned, and to further provide tipand base securing means which will maintain the parts in tight assembly.However, such efforts have not met with any considerable degree ofsuccess for various reasons. In some instances, the opposed stresstransferring surfaces of the tip and base have been improperly locatedor are of insufiicient area, and in other cases the formation of suchsurfaces has made it difiicult and expensive if not actually impossibleto grind or machine them sufiiciently to bring about adequatestress-transferring engagement.

Then, too, those of the prior art teeth which may be somewhat betterthan others as regards stress transfer from tip to base are difficult toassemble and separate especially in large sizes, due to an over tight orjam fit of the parts in certain areas even though proper stress transferis lacking in other areas.

And as regards tip and base securing means, as for instance, the wedgingkey type which is driven into place to, draw the tip onto its base seat,it has heretofore always heenarranged in reference to contactingstress-transmitting tip and base parts, as to be in shear so as tospeak.

This means that said key is subject to bending transversely of itslongitudinal axis when driven in, as well as in service. Therefore, theaforementioned loosening of tip and base occurs and the resultantpounding action means ultimate loss of the tip if it is not replaced.

Once a wedge form key has been bent so that a permanent set is acquired,it is useless. In my aforesaid copending application, I have sought toovercome key bending by employing an oversized heavy duty key but thisis expensive in metal expenditure and also requires aligned passages ofconsiderable size through the tip and base which tend to weaken same.

In view of the fact that the top and bottom wings of digging tips tendto spread in service prior developers in the art have found it necessaryto provide the tip with either a heavy gauge wing-connecting central webor wing-connecting side walls of substantial thickness. Also, suchwing-connecting webs or side walls have to be especially heavy when abase-carried wedging key is to be projected therethrough to draw the tiponto the base seat and retain it there. Thus, wing-connecting Webs orside walls, as I have found, add unnecessarily to the weight of the tipand consequent expense of same, and are dispensed with in my presentdevelopment, as well as in that of my aforenoted application, withoutsacrifice of efliciency.

Therefore the primary objects of my present invention are to overcomethe objections aforenoted and to provide a lighter and more serviceabledigging tooth of the class indicated, but which is of simple and durableconstruction while providing adequate tip-to-base stress transfer, and anovel tip and base securing means which will assure tightness of saidparts.

It is also an aim of the invention to provide a tooth which isrelatively inexpensive to manufacture in that it requires but a minimumof easily accomplished machining of opposed stress-sustaining portions,and wherein the digging tip can be readily applied to or removed fromthe tooth base even as to large sized teeth, the arrangement of partsalso being such that the tip and base securing member is subjected totransverse compression loads in service and is free of any shear loadswhich will tend to longitudinally bow or bend it in service so as toresult in looseness of the parts.

More specifically, the invention contemplates in a removable V-formdigging tip having vertically divergent rearwardly extending Wings, theprovision of opposed and parallel rearwardly extending wing-carried lugswhich are of wedge form in cross-section and are received incorrespondingly shaped base nose-provided seats, there being a removabletooth base-carried key cooperating with said wedge form lugs to retainthe tooth base and tip in tight assembly, and which key has acompression relationship between opposed lug and base portions so as tobe freed of stresses tending to longitudinally bow or bend it inservice.

Also, having reference to the base nose-provided seats for thewedge-form tip lugs, mentioned in the preceding paragraph, it is an aimof the invention to provide novel means whereby the slanted side wallsof said seats can be easily and quickly machined to make adequate stressreceiving engagement with the related sides of the wedgeform lugs of thedigging tip.

Other objects and advantages of the invention will be developedhereinafter, or will be obvious to those versed in the art, referencebeing had to the accompanying drawings which illustrate now-preferredexamples of my inventive concept. It is to be understood, however, thatthe disclosures herein are to be taken as illustrative rather thanlimitative, as the invention is susceptible of other mechanicalexpressions within the sprit and scope of the subject matter claimedhereinafter. l i

In the drawings, wherein the same reference characters have been used todesignate the same parts wherever they appear throughout the severalviews- Fig. 1 is a side elevational view, partly in longitudinal sectionof a tooth embodying my invention;

Fig. 2 is a longitudinal sectional view through the tooth and showingthe seated stress-sustaining lugs of the digging tip and the engagementof same by a wedge action key for retaining the digging tip and baseassembled;

Fig. 3 is a fragmentary perspective view illustrating the commencementof assembly of the digging tip and base section, the dotted linesindicating the permissible initial lateral play between the parts whichfacilitates the as sembly operation;

Fig. 4 is a cross-sectional view taken on the line 4-4 of Fig. 2;

Fig. 5 is a perspective view of the digging tip;

Fig. .6 is a fragmentary perspective view showing the forward tipseat-providing end of the base section of the tooth;

Fig. 7 is a plan view of the tip and base-securing key and its retainer;

Fig. 8 is a sectional view of a portion of the assembled tip and basetaken on the line 88 of Fig. 2, and showing the securing key with itsretainer in operative engagement in a recess in the side of the basenose;

Fig. 9 is a section on line 99 of Fig. 2;

Fig. 10 is a central vertical sectional view through a modified form oftooth;

Fig. 11 is a sectional view taken on line 11-11 of Fig. 10; and

Figs. 12 and 13 are sectional views taken on the lines 12-12 and 13-13,respectively, of Fig. 10.

Referring to the drawings by reference characters, numeral 10 indicatesthe base section of the tooth, the rear end of which is bifurcated asusual for mounting on the digging lip (not shown) of a power shoveldipper, drag bucket or other item of excavating equipment. As shown inFigs. 1, 2 and 6, the tooth base 10 has, at its forward end, the noseprojection 11 which is coextensive in Width with the base and providesthe seat for the separable digging point or tip 12.

In the illustrated embodiment, the top and bottom surfaces of the nose11 taper inwardly toward the rounded forward end thereof. The top andbottom surfaces and rounded end of nose 11 make contiguous engagementwith the rounded inner end of the tip-provided seating recess 14 that isbounded top and bottom by the vertically diverging rearwardly extendingwings .13 of tip 12. As indicated in Fig. 2, these tip-provided wings 13are coextensive in width with the tip 12 and the base 10, and Figs. 1and 2 show how the opposed inner surfaces of the respective wings 13incline outwardly as at 13a, adjacent to the rear ends thereof. Theserear wing end surfaces 13a will ordinarily be initially spaced from thecorrespondingly inclined top and bottom shoulder-providing surfaces 11aat the rear end of base nose 11 when the latter is fully engaged in theseating recess 14 of tip 12. However, if the tip seat 14 is oversized orif the nose 11 has become worn as the result of many tip applicationsand removals, the opposed inclined surfaces 11a, 13a will camminglyengage to tend to draw wing carried wedging lugs 15 more tightly againstthe side Walls 19 of their base nose-provided seats 18. Engagement of11a, 13a will rarely occur.

Referring now to Figs. 2, 4 and 5, it will be noted that the digging tip12 provides, as an integral part thereof and between wings 13, the twoaforementioned vertically spaced and parallel rearwardly extending lugs15 whose rear ends project beyond the rear ends of said wings as bestshown in Fig. 2. These lugs 15, as hereinabove indicated, are wedge-formin cross-section and are of substantial Width as shown in Figs. 4 and 5,they being located adjacent the inner surfaces of the respective wings13 at points approximately midway be- '4 a tween the sides of thelatter. It is particularly important to note that the wedge-form of thelugs 15 is achieved by substantially plane side surfaces 15a which slantin the direction of the adjacent wing 13. It is also important to notethat said lugs 15 increase in thickness rearwardly to outwardly beveledwing ends 13a, so as to provide substantial mid area reinforcement forsaid wings as a means to resist outward bending of same in service.

Figs. 2 and 5 also show the lugs 15 as having opposite key-receivingcutouts 16 extending across their opposed surfaces and which will bereferred to again hereinafter.

In further carrying out the invention, 1 provide the digging tip 1'2with the integral boss 17 which is located at the-curved inner end ofthe nose-receiving recess 14 approximately mid-way between the wingsides. This boss 17 is an integral part of the lugs 15 adjacent theinner ends of the latter (see Figs. 2 and 5), so as to provide furthermid area reinforcement for the tip wings 13 and for another purposewhich will be presently understood. 7

Coming now to the digging tip seating and sustaining formations of thenose portion 11 of the tooth base 10, and turning to Figs. 2, 3, 5 and6, it will be observed that the top and bottom surfaces of the nose -11each provide an earlier mentioned rearwardly extending and groove-formlug-receiving seat 18. These seats 18 are open at their forward ends andare defined by the undercut side walls 19 which substantially conform tothe slant of the lug sides 15a and flare laterally outward (19a) at theentry ends of the sockets to facilitate insertion of lugs 15. The rearend of each lug-receiving seat 18 terminates in a lug end-receiving andsustaining socket 18a, as best shown in Fig. 2.

Also, as indicated in Figs. 2, 3 and 6, the rounded outer end of thenose 11 has the cutout-provided seat 20 which snugly receives the boss17 of tip decess 14. This interengagement of boss 17 with nose seat 20cooperates with the lugs 15 and their seats 18, 18a to prevent relativelateral movement of the base 10 and tip 12 in service after the partshave been assembled.

In the illustrated embodiment of the invention (see Figs. 2, 4, 7 and8), I employ the channel-form wedge form key 23 as the means forsecuring the tip 1'2 and base 10 in tight rigid assembly. The key 23 isprojected through the transversely extending nose-provided cross passage21, as indicated in Figs. 1 and 2, to bring its channel wall edges 23a.into actuating bearing contact with the rear shoulders 16a which areprovided by, the opposed lug notches 16. The bight portion of the key23, as indicated in Figs. 2 and 4, has uninterrupted bearing engagementwith the forward wall 21a of the nose passage so as to be supportedthereby throughout the width of nose portion 11, and particularlyopposite the engaged shoulders 16a of the wing-carried lugs 15.

As will be appreciated from the foregoing, the key 23, as shown in Figs.2 and 9, is in such fore and aft compression between the forward wall21a of nose passage 21 and the rear shoulders 16a of lug notches 16 thatit is not subjected in service to longitudinal bowing or bendingstresses as are prior art keys and thus effectively prevents looseningof the tip 12 and base 10. As seen in Fig. 2, the top and bottommargin-adjacent areas of the bight portion of key 23 are not backed bythe forward wall 21a of nose passage 21. However, the body of key 23will obviously be heavy enough so that there will be no load-induceddeformation thereof at the site of unsupported bight areas along linesparalleling its longitudinal axis.

Referring again to the lugs 15 and to the groove-form nose-providedseats 18 therefore, one of the problems left unsolved by the prior art,but which is solved by my invention, is to so form the interengagingstress-sustaining parts of a tooth base and digging tip as to readilyadmit of necessary grinding or machining of same to obtain a proper fitand avoid looseness. This I achieve by provision of the broad, unbrokenand preferably plane wedging sides 15a of the lugs 15; and also by thedrilled or cored longitudinal bores 24 (see Figs. 4 and 6) which openlaterally to the wedge-receiving seats 18 at the junctions of side walls19 with the bottom walls thereof. These bores 24 extend the full lengthof the respective seats 18 and related lug end-receiving sockets 18a,and as will be appreciated, they enable a grinding tool to properly actupon the full width of the groove bottoms and adjacent wedging walls 19,19a.

The outward flaring (19a) of the side walls 19 at the entry ends of thelug seats 18 also facilitates grinding of the surfaces of the latter andparticularly at the socketproviding inner ends 18a of the same. Theflared entry ends of seats 18 also is important in that it facilitatesassembly of the tip 12 and base 10 by admitting of limited initiallateral rocking of the former, and conversely disassembly is facilitatedtoo.

To retain channel form wedging key 23 in place after it has been drivenhome, I provide the locking pin 25 of Figs. 7, 8 and 9. The majorportion of pin 25 is received in the channel between key walls 23a andits hooklike inner end 25a is anchored in the transverse hole 27 in key23, which hole 27 communicates with the surface groove 26in the bightwall of the key. The bill terminal of the pin hook 25a seats in groove26 as shown in Figs. 8 and 9. The outer end 2512 of pin 25 is permittedto project beyond the key end as the key is being driven home to drawtip 12 onto nose 11. After key 23 has been driven home, the projectingend 25b of pin 25 is hammered into the surface recess 28 of nose 11 toretain key 23 in place.

Referring to Fig. 2, a further important feature of the invention is thecoaction of the outer or. wing-adjacent horizontal lug surfaces b withthe opposed inwardly inclined wall surfaces 18b of the lug end-receivingsockets 18a. As shown in Fig. 2, the initial seating of the tip 12 onthe base nose 11 leaves a space between wing ends 13a and the opposedbase shoulders 11a andlikewise between the free ends of the lugs 15 andthe inner ends of lug sockets 18a so as to admit of subsequentre-tightening of the tip 12 on base nose 11 by inward actuation of wedgekey 23. Such further inward actuation of tip 12 results in wings 13being urged tighter against the top and bottom nose surfaces by theaction of the inwardly inclined socket surfaces 18b against the opposedlug surfaces 15b which, as shown, are in an intersecting plane which inthe illustration happens to parallel or substantially parallel thelongitudinal axis of the tooth.

' Bearing contact between the aforenoted surfaces 15b, 18b is furtheraccentuated if and when the cam form Wing end and base shoulders 13a,11a are brought into engagement. I From the foregoing it will beapparent that without decreasing digging surface area, I provide alighter weight and hence less expensive digging tip than heretoforeknown, and further, one which provides ,a simplified tip and baseconnection which will not work loose in service as the result of bendingexertion stress on key 23 or otherwise. A long lived tip 12 is thusprovided.

Also, as will be appreciated, the lug and seat arrangement 15, 18 takesadvantage of the spreading tendency of wings 13 in service to effect atightening of Same and tip 12 on nose 11.

Additionally, it is evident that the lugs 15 have the further functionof providing the, notch shoulders 16a above and below the tip (12) axisto be engaged by key 23 to draw the tip 12 onto nose 11. Application ofkey (23) pressure to lug shoulders 16a at opposite sides of the tip axisand near the wings .13 accomplishes a saving in the force required todraw tip 12 onto nose 11.

I The fact that key 23 is not subject to loads calculated to bow or bendit longitudinally in service enables me to use a lighter key, thussaving metal.

Figs. 10-14 disclose a modified form of the invention involving, as inmy aforenoted application, ,a vertically extending wedging key 40 fordrawing the digging tip 32 onto the nose portion 31 of the tooth base30. However, in contradistinction to the key of said application thevertical key 40 of my present invention does not have to be an oversizedheavy duty key to avoid longitudinal bowing or bending in service. Thisis so because my present key 40 is in fore and aft compression acrosssaid axis between portions of the base-provided nose 31 and the rearshoulders 43a which are provided by notches 43 in the diggingtip-carried lugs 35 (see Figs. 10 and 11) as will be better understoodhereinafter.

,The tooth of the modified form of the invention (Figs. 10-14) differsvery little from that of Figs. 1-9. Thus the modification involves thebase section 30 having the forwardly extending nose 31 which fitsagainst the concaved seating area 34 between the divergent wings 33 ofdigging tip 3'2.

The digging tip 32 has the rearwardly extending wingcarried lugs 35 ofwedge form cross-section which are received in forwardly openingnose-provided seats 38 whose rear ends terminate in sockets 38a havinginwardly inclined outer cross walls 38b corresponding to 18b of Fig. 2.The rear ends of lugs 35 enter sockets 38a and the outer surfaces 35b ofthe lugs 35 Wedge against the inclined socket walls 38b, as do 15b, 18bin Fig. 2, so as to tend to force wings 33 firmly against the relatedtop and bottom surfaces of nose 31.

In the modification the outer ends of the undercut side walls 39 of thelug-receiving nose-provided seats 38 have a curved outward flare 39a inopposite directions (see- Fig. 11) instead of being inclined outwardlyin substantially a straight line 19a. This is to better facilitatedesirable initial lateral play between base 30 and tip 32- Whenassembling.

Furthermore, in the modification the boss 17 of Figs. 2 and 3 and itsreceiving nose end notch 20 are dispensed with and are replaced byaligned centrally located bosses 37 at the outer ends of the respectivenose-provided lug seats 38, which bosses 37 work in the longitudinallyextending lug grooves 35a as shown in Figs. 10, l1 and 12. The entryends of grooves 35a are somewhat wider than the related bosses 37 so asto cooperate with the outwardly flared entry ends 39a, 39a of lug seats38 in admitting. of initial limited lateral play of the tip 32 whenassembling same with base 30. However, when the tip 32 is furtheradvanced on nose 31 bosses 37 make a snug fit in lug grooves 35a tosustain the tip and base 30', 31 against relative lateral movement justas do boss 17 and nose end notch 20 in Fig. 2.

It is further to benoted that the fiat shoulder-providing inner ends 37aof bosses 37, as shown in Fig. 10, are in plane with the front wall 42aof the vertical wedging. key-receiving cross passage 42 through noseportion 31.. This key passage 42 passes through the mid-portion oflug-seats 38 between side walls 39 and said passage 42' registers withthe wing holes 41 of digging tip 32. Thus, 37a, 42a, 37a provide anelongated bearing or backing surface for the narrowed 'bight portion ofthe channelform wedging key 40 as shown in Fig. 11. As also shown inFigs. 10 and 11, the .outer edges of the outwardly inclined walls ofchannel key 40 bear against the rear shoulders 43a of the respectivepairs of opposed lug notches 43. n

Thus, Fig. 11 considered with Fig. 10 makes it plain that each lug 35has the opposed notches 43 at opposite sides of its boss-receivinggroove 35a. It is further clear from these views that when wedge key 40is driven into its passage 41, 42, the load from the rear lug notchshoulders 43a will be transmitted by the key walls 400. to the basenose-provided-boss shoulders 37a via the key bight, and of course theconverse is true too.

Thus, Figs. 10 and 11 show that the load sustaining portion. of wedgingkey 40 between the two sets of opposed lug notch and boss-providedshoulders 43a, 37a,

'7 respectively, is in fore and aft compression transversely of itslongitudinal axis and accordingly does not have to be made oversized inorderto prevent longitudinal bowing or bending as is true of the key ofmy aforenoted application. Accordingly, key 40 will not bend or bowlongitudinally in service to allow the tip and base to work loose.

A locking pin 45 is, or may be, carried by the small end of key 40 toretain it in place as does the pin 25 of Figs. l-9. Also, the rear wingends 33a are outwardly inclined as are the opposed nose shoulders 31acorresponding to 11a, 13a of Figs. 1 and 2, and for the same purpose.

Also to facilitate milling of the lug seats 38 the intersections of sidewalls 39, 3911 with the seat bottoms can be cored out as at 44,corresponding to 24 in Figs. 3 and 6. As a matter of fact the structuralarrangements herein described eliminate the necessity for milling orgrinding of any surfaces except those of the lugs 15 (or 35)- and theirseats 18 (or 38). This makes for a great saving in manufacturing costwithout loss of efiiciency. Also the cored out seat side portions 24(Fig. 4) and 44 (Fig. 12) constitute friction-eliminating relief areasreceiving lower side edges of the lugs 15 (or 35). The term transverelyas applied to the keyreceiving passage 21 is not to be construed ascovering the vertical passage 41, 42 of Fig. 10.

Having thus described my invention, what I claim is:

l. In a dipper tooth or the like, providing a base section having atip-mounting nose at its forward end, a detachable V-form digging tiphaving rearwardly diverging top and bottom wings between which said nosefits, a rearwardly extending lug carried by opposed surfaces of each ofsaid tip wings and arranged in spaced parallelism to each other onopposite sides of the longitudinal axis of said tip, said tip-mountingnose providing ,top and bottom forwardly opening socket-form seatsreceiving said respective lugs, the opposed surfaces of said lugs havingaligned transversely extending cutouts providing rear shoulders, saidnose having a transverse keyreceiving cross passage which is open toopposed transverse portions of said nose-provided seats between the endsof the latter, said lug cutouts being open to said key passage when thetip is partially seated on said nose, and a longitudinally wedge formkey insertable in said passage and providing rear longitudinal portionsto engage said lug cutout-provided shoulders to actuate the tip ontosaid nose and retain itin place thereon, and saidpassage providingforwardly located key-sustaining wall means disposed in co-planarload-sustaining and key-compressing opposition to said lug shouldersalong a portion of the length of the key in planes extending parallel tothe longitudinal axis of the key whereby the key will be in tranversecompression in service and will not tend to bend or bow longitudinally.

2. In a dipper tooth or the like providing a base section having atip-mounting nose at its forward end, a detachable V-form digging tiphaving rearwardly diverging top and bottom wings between which said nosefits, a rearwardly extending lug carried by opposed surfaces of each ofsaid tip wings and arranged in spaced parallclism to each other onopposite sides of the longitudinal axis of said tip, said tip-mountingnose providing top and bottom forwardly opening seats receiving saidrespective lugs, said lugs and seats being wedge form in cross-sectionand providing plane contiguously engaging side wall surfaces so as totighten the engagement of the lugs in said seats under attempted outwardspreading action of said wings, the opposed surfaces of said lugs havingaligned transversely extending cutouts providing rear shoulders, saidnose having a transverse keyreceiving cross passage which is open toopposed transverse portions of said nose-provided seats between the endsof the latter, said lug cutouts being open to said key passage when thetip is partially seated on said nose,

a longitudinally wedge form key'insertable in said passage and providingrear longitudinal portions to engage said lug cutout-provided shouldersto actuate the tip onto said'nose and retain it in place thereon, andsaid passage providing key-sustaining wall means disposed in co-planarload-sustaining and key-compressing opposition to said lug shouldersalong a portion of the length of the key in planes extending parallel tothe longitudinal axis of the key whereby the key will be in transversecompression in service and will not tend to bend or bow longitudinally.

3. A dipper tooth or the like providing a base section and a detachabledigging tip carried thereby, the base section having a forwardlyextending tip-seating nose providing top and'bottom surfaces taperingforwardly toward its outer end, the tip having rearwardly extending topand bottom wings providing an open sided recess therebetween receivingand mounting the tip on said nose, a pair of vertically spaced andparallel Wing carried lugs of wedge-form cross-section providing broadopposing surfaces, said lugs located at opposite sides of thelongitudinal axis of the tip and extending from adjacent the forward endof said tip-provided recess beyond the rear ends of said wings, and eachof said lugs providing longitudinally coextensive and substantiallyplane sides tapering transversely of said lugs in the direction of theadjacent wing, the top and bottom surfaces of said nose portion havingrearwardly extending wedge-form seats having bottom walls and undercutside walls, said seats being open at their forward ends and receivingthe respective lugs, the rear end of each seat terminating in a socketreceiving the rear end of one of said lugs, the fully engaged lugs andseats drawing said wings against adjacent nose surfaces while preventingrelative lateral movement of said base and tip, a rearwardly extendingboss provided by said tip at the forward end of said nosereceivingrecess, said boss being integral with said lugs and located inwardly ofthe sides of the latter, the forward end of said nose having a seatingrecess snugly receiving said tip boss to cooperate with the interengagedlugs and seats to prevent relative lateral movement of the base and tip,said base-provided nose having a transverse key-receiving cross passagewhich is open to opposed portions of said nose-provided seats, betweenthe ends of the latter, forwardly facing cutout-provided shoulders insaid lugs and substantially aligned transversely of the latter, and awedge-form key insertable in said passage to engage said lug shoulders'to actuate the tip onto said nose, and said passage providingkey-sustaining wall means disposed in co-planar load-sustaining andkeycompressing opposition to said lug shoulders along a portion ofthelength of the key in planes extending parallel to the longitudinal axisof the key whereby the key will be in transverse compression in serviceand will not bend or bow longitudinally.

4. The combination set forth in claim 1, the lugs and seats havinginterengaging side walls, and the inner surfaces of the wing ends andthe adjacent underlying opposed base section provided surfaces beingrearwardly and outwardly tapered with respect to the respective Wingaxes whereby engagement of said surfaces tends to draw the lug and seatside walls into tighter engagement with one another. 7

5. The combination set forth in claim 2, and wherein the nose-providedlug seat side walls flare outwardly at the entry end of said seatswhereby to admit of initial lateral rocking of the tip when the latteris being assembled on the tooth base, and also to facilitate oper-'ail(l)l11 of a milling tool upon inner portions of the seat wa s.

6. The combination set forth in claim 2, and each of said nose-providedlug seats having a bottom wall and providing at each side a laterallyextending and longitudinally coextensive recess opening from both thebottom wall and related side wall whereby to provide afriction-eliminating rell'fr area into which the lug side and"bo'ttoni-provided edge extends.

7. A dipper tooth or the like comprising a base section and a detachabledigging tip, the base-section having a nose' providing separate top andbottom forwardly opening seats and the tip having a nose-receivingrecess and a pair of rearwardly extending lugs projecting therefrom atopposite sides of the longitudinal axis of the tip and engageable insaid nose seats, and the entry ends of said seats having outwardlyflaring side walls whereby to admit of initial lateral play. of the lugswhen the tip and'base are being assembled, said nose portion providing across passage extending transversely therethrough in part open toopposed portions of said nose-provided seats'between the ends of thelatter, a removable wedgeiorni key insertable through said pasfforwardly fac'inglug-pr'ovided shoulders projectinto said "passage 'and"engaged "by rear longitudinal portions of said key to"forcethe tip ontosaid nose, and the latter having forward key-sustaining passage wallprovided portions arranged in co-planar load-sustaining andkey-compressing opposition to said lug shoulders alopg a portion of thelength of the key in planes exteriding'pafallel to-the longitudinal axisof the key whereby the key will be in transverse compression and willnot tend to bend or bow longitudinally in service.

8. A dipper tooth or the like comprising a base section and a detachabledigging tip, the base section having a nose providing separate top andbottom forwardly opening seats and the tip having a nose-receivingrecess and a pair of rearwardly extending lugs projecting therefrom atopposite sides of the longitudinal axis of the tip and engageable insaid nose seats, said nose portion providing a transversely extendingkeyway therein, said keyway having an intermediate portion open toopposed portions of said seats, a removable wedge-form key insertable insaid keyway, and forwardly facing lug-provided shoulders engaged by saidkey to force the tip onto said nose, and the keyway providingkey-sustaining wall portions arranged in co-planar load-sustaining andkeycompressing opposition to said lug shoulders transversely of thelongitudinal axis of the key.

9. In a dipper tooth or the like comprising a base section and adetachable digging tip-providing section carried thereby, said sectionshaving interfitting lug and socket portions, a securing key extendingtransversely through portions of said interfitting lug and socketportions, said key being wedge-form in longitudinal section and alsobeing of channel cross section to provide side walls and a bight wall, aseat provided in the outer surface of said bight wall of the key andopening into the groove between said side walls, a key-securing pinseated in and projecting from the outer end of said channelprovidedgroove, the groove-housed portion of said pin lying inwardly of theplane of the outer edges of the channel side walls so as to be protectedthereby, said securing pin having a laterally bent inner end engaged insaid bight-wall-provided seat, and said base section having a surfacerecess into which the outer end of said pin is bent after the key hasbeen driven in place whereby to retain the key in operative position.

10. The structure set forth in claim 8 and said wedge form key beingchannel-form in cross section whereby to provide bight-connectedsidewalls, the respective side wall edges of said key engaging saidlug-provided shoulders at opposite sides of the longitudinal axis of thetip, and the bight portion of said key engaging said sustainingkeyway-provided wall.

11. In a digging tooth for excavating dippers and the like, comprisingseparable but functionally integral base and digging point-providingsections having interfitting lug and socket-provided load-absorbingportions to prevent relative shifting of the sections under diggingstressproduced loads, there being a passageway extending transverselythrough said base and digging point-provida a [1.6 ing sections at thesite of: said load-absorbing portions and approximately midway betweenopposite longitudinal edges of thetooth; the combination of a key whichis wedge form in longitudinal section and of channel cross section andinserted in said passageway, the load-absorbing portion of said pointsection providing shoulders at opposite sides of thetoot'n axis andsubstantially normal thereto, Said shoulders projecting into saidpassageway at the rear side of the latter, said channel form keyproviding a bight wall and side walls with the edges of differentones ofthe key side walls engaging said shoulders, and the base sectionproviding key bight-engaging portions arranged in co-planarload-receiving and keycompressing opposition to the aforementioned pointsection provided shoulders along a portion of the length of the key inplanes extending parallel to the longitudinal axis of the key,whereby'the tip section will be actuated into and held in tighta ssembly with the base section and the key' will be in transversecompression so that it will not tend to bend or how longitudinally inservice. '12. In adippertooth 'or, the like comprising a base sectionand aV-form digging point-providing tip section having top and bottomwings, the forward part of the base section'and the space between saidwings providing interengaging seating surfaces, two pairs oflongitudinally extending and interfitting stress transfer portionsprovided by said sections between said wings, one of said pairs locatedabove and the other pair below the longitudinal axis of the diggingpoint-providing section, the forward part of said base section providinga transversely extending keyway therein, said keyway having anintermediate portion extending through both of said pairs ofinterfitting stress transfer portions when said sections are assembled,each of the stress-transfer portions of said tip section having arearwardly located and forwardly facing shoulder extending into saidkeyway, a wedge member insertable in said keyway and having rear surfaceportions engaging each of the tip section-provided shoulders to draw thetip section onto said base section, and the base section keywayproviding forwardly located and rearwardly facing wall portions arrangedin coplanar load-sustaining and key compressing opposition to said tipsection-provided shoulders along a portion of the length of the key inplanes extending parallel to the longitudinal axis of the key, wherebyto prevent longitudinal bowing or bending of the wedge member inservice.

13. In a dipper tooth or the like comprising a base section and a V-formdigging point-providing tip section having top and bottom wings, theforward part of the base section and the space between said wingsproviding interengaging seating surfaces, two pairs of longitudinallyextending and interfitting stress transfer portions provided by saidsections between said wings, one of said pairs located above and theother pair below the longitudinal axis of the digging point-providingsection, the forward part of said base section providing a cross passageextending therethrough, said cross passage having an intermediateportion extending through both of said pairs of interfitting stresstransfer portions when said sections are assembled, each of thestress-transfer portions of said tip section having a rearwardly locatedand forwardly facing shoulder extending into said cross passage, a wedgemember insertable in said cross passage and having rear surface portionsengaging each of the tip section-provided shoulders to draw the tipsection onto said base section, and the base section-provided crosspassage having forwardly located and rearwardly facing wall portionsarranged in co-planar load-sustaining and key compressing opposition tosaid tip sectionprovided shoulders transversely of the plane of thelongitudinal axis of said wedge member, whereby the wedge member will besustained against longitudinal bowing or bending in service.

14. In a dipper tooth or the like comprising a base section and adetachable diggingtip-providing section carried thereby, said sectionshaving longitudinally extending interfitting lug and socket portionswith the lug portions carried by the tip-providing section, there beinga base section-provided cross passage extending through saidinterfitting lug and socket portions, said cross passage being open toopposed socket portions between the ends of the latter, forwardly facinglug portion-provided shoulders extending into said passage, a wedge-formsecuring key in said passage and making rearward bearing engagement withsaid lug portion-4 provided shoulders, and said mase section-providedpassage providing key-sustaining wall portions at the forward side ofsaid key, the key-engaged lug portion-provided shoulders and at leastcertain of said key-sustaining wall portions of the basesection-provided passage being in co-planar fore and aft keycompressingopposition to one another transversely of the plane of the longitudinalaxis of the key whereby the key will be sustained against longitudinalbowing or bending in service.

15. The combination set forth in claim 14, and said key being wedge-formin longitudinal section and of channel-form in cross section with theedges of the channel-provided walls making bearing engagement with thelug portions.

References Cited in the file of this patent UNITED' STATES PATENTS1,188,480 Pemberton June 27, 1916 1,270,670 Stone June 25, 19182,230,424 Bruton Feb; 4, 1941 2,251,169 Seal July 29, 1941 2,307,359Crawford Ian. 5, 1943 2,339,128 Younie Ian. 11, 1944 2,709,941 LarsenJune 7, 1955 FOREIGN PATENTS 103,025

Great Britain Ian. 11, 1917

